Id4 Suppresses the Growth and Invasion of Colorectal Cancer HCT116 Cells through CK18-Related Inhibition of AKT and EMT Signaling.

Id4 is one of the inhibitors of DNA-binding proteins (Id) and involved in the pathogenesis of numerous cancers. The specific mechanism underlying the Id4-mediated regulation of proliferation, invasion, and metastasis of colorectal cancer (CRC) cells is still largely unclear. In the present study, results showed CRC cells had a lower baseline Id4 expression than normal intestinal epithelial NCM460 cells. In order to explore the role of Id4 in the tumorigenicity, CRC HCT116 cells with stable Id4 expression were used, and results showed Id4 overexpression arrested the cell cycle at the G0/G1 phase, inhibited the cell proliferation and the colony formation, as well as suppressed the migration and invasion. In the in vivo model, Id4 overexpression inhibited the tumor growth and metastasis in the nude mice. Furthermore, Id4 overexpression upregulated the expression of proteins associated with cell proliferation, inhibited the PI3K/AKT pathway, and suppressed epithelial-mesenchymal transition (EMT) of HCT116 cells. Moreover, Id4 significantly decreased cytokeratin 18 (CK18) expression, but CK18 overexpression in Id4 expressing HCT116-Id4 cells rescued the activation of AKT, p-AKT, MMP2, MMP7, and E-cadherin. Collectively, our study indicated Id4 may inhibit CRC growth and metastasis through inhibiting the PI3K/AKT pathway in a CK18-dependent manner and suppressing EMT. Id4 may become a target for the treatment of CRC.

Somatostatin Octapeptide Inhibits Cell Invasion and Metastasis in Hepatocellular Carcinoma Through PEBP1.

BACKGROUND/AIMS: Hepatocellular carcinoma (HCC) is a major threat to human health. The condition carries a high risk of death; 45% of new cases occur in China. Surgical resection is the first choice for treatment of HCC, but 30.9% of patients experience recurrence within 6 months after the operation. To improve patient survival, we must determine how to reduce the probability of recurrence and metastasis and elucidate the underlying mechanism of disease. We therefore studied the effect of somatostatin octapeptide (octreotide) on the invasion and metastasis of HCC. METHODS: The migration and invasion cytological tests were used to detect the effect of octreotide on liver cancer cells (SK-Hep-1 and HepG2). PEBP1 RNAi was used to knockdown expression. Invasion and metastasis were measured with transwell migration and wound-healing assays. Western blotting was used to detect changes in levels of PEBP1 and invasion pathway proteins after octreotide treatment. The effect of octreotide was studied in vivo by establishing a pulmonary metastasis model using SK-Hep-1 cells in nude mice. In-vivo bioluminescence imaging and hematoxylin and eosin staining of lung tissue were used to verify the results. RESULTS: Increasing concentrations of octreotide were progressively more effective in halting the invasion and metastasis of liver cancer cells. Octreotide may upregulate PEBP1, TIMP-2, and E-cadherin while downregulating MMP-2 and Twist to inhibit cell invasion and metastasis. And downregulation of PEBP1 would also change the expression of MMP-2, TIMP-2 and Twist. The in-vivo experiments showed no cancer cell metastasis in 4 of the 6 mice in the octreotide-treatment group, while all of the mice in the control group displayed pulmonary metastasis of human HCC cells. And the survival period of the mice in the octreotide-treatment group was significantly prolonged. CONCLUSIONS: Octreotide may weaken invasion and metastasis through the upregulation of PEBP1. Octreotide may reduce the risk of recurrence and metastasis after surgery for liver cancer.

Metabolomics identifies metabolite biomarkers associated with acute rejection after heart transplantation in rats.

The aim of this study was to identify metabolite biomarkers associated with acute rejection after heart transplantation in rats using a LC-MS-based metabolomics approach. A model of heterotopic cardiac xenotransplantation was established in rats, with Wistar rats as donors and SD rats as recipients. Blood and cardiac samples were collected from blank control rats (Group A), rats 5 (Group B) and 7 days (Group C) after heart transplantation, and pretreated rats 5 (Group D) and 7 days (Group E) post-transplantation for pathological and metabolomics analyses. We assessed International Society for Heart and Lung Transplantation (ISHLT) grades 0, 3B, 4, 1 and 1 rejection in groups A to E. There were 15 differential metabolites between groups A and B, 14 differential metabolites between groups A and C, and 10 differential metabolites between groups B and C. In addition, four common differential metabolites, including D-tagatose, choline, C16 sphinganine and D-glutamine, were identified between on days 5 and 7 post-transplantation. Our findings demonstrate that the panel of D-tagatose, choline, C16 sphinganine and D-glutamine exhibits a high sensitivity and specificity for the early diagnosis of acute rejection after heart transplantation, and LC-MS-based metabolomics approach has a potential value for screening post-transplantation biomarkers.

Tumor MICA status predicts the efficacy of immunotherapy with cytokine-induced killer cells for patients with gastric cancer.

In this study, we determine the relationship between the expression of major histocompatibility complex class I chain-related gene A (MICA) in gastric cancer tumors after D2 gastrectomy and the clinical outcome of a CIK-containing adjuvant therapy. Ninety-five consecutive patients with gastric cancer after D2 gastrectomy who received adjuvant chemotherapy combined with CIK cell therapy were enrolled. The MICA expression of their tumors was determined by immunohistochemistry (IHC). High expression of MICA protein was documented by IHC in 38 of 95 tumor samples (40.0 %). The MICA status was significantly associated with the age and stage, p = 0.008 and 0.023, respectively. Analysis of NKG2D on in vitro expanded CIK cells showed that the percentages of NKG2D+ in CD3+/CD56+, CD3-/CD56+, and CD3+/CD8+ cells populations were 97.2 ± 1.4, 97.9 ± 1.8, and 95.6 ± 2.1 %, respectively. For patient with high MICA-expressing tumors, the median DFS and OS were longer than for the patients with tumors with low expression of MICA; 46.0 versus 41.0 months (p = 0.027), and 48.0 versus 42.0 months (p = 0.031), respectively. In a multivariate analysis, stage and MICA expression were independent prognostic factors for DFS and OS. Our findings show that adjuvant chemotherapy plus CIK therapy treatment is a promising modality for treating gastric cancer patients after D2 gastrectomy. Especially, those who have tumors with high expression of MICA were more likely to benefit from such a treatment strategy. Subsequent studies in clinical trial cohorts will be required to confirm the clinical utility of these markers.

Decreased expression of liver-type fatty acid-binding protein is associated with poor prognosis in hepatocellular carcinoma.

BACKGROUND/AIMS: The purpose of this study was to assess liver-type fatty acid-binding protein (L-FABP) expression and its association with clinicopathological features in hepatocellular carcinoma (HCC). METHODOLOGY: L-FABP mRNA expression in 57 samples of HCC and corresponding adjacent liver tissue and 8 normal liver tissue samples were examined by real-time reverse transcriptase (RT)­PCR analyses. Tissue microarray technique and immunohistochemistry (IHC) were used to detect the expression of L-FABP in 163 HCCs. The association between L-FABP expression and the clinicopathological factors and prognosis was analyzed. RESULTS: The average expression of L-FABP mRNA was 0.233 in the HCC tissues, 1.407 in the peri-carcinoma tissues, and 1.0 in the normal liver tissues. IHC analysis showed that there were 47% (76/163) HCCs exhibited weak or even no immunoreactivity of L-FABP. The L-FABP expression in HCC showed significant associations with preoperative levels of AFP (p=0.039), tumor size (p=0.026), histological grade (p=0.000), differential degree (p=0.000), vascular invasion (p=0.016), capsular invasion (p=0.029) and recurrence (p=0.004). Patients with L-FABP high-expression showed better prognosis than patients with L-FABP low-expression (p=0.008). CONCLUSIONS: L-FABP was downregulated in HCC and could be served as a promising prognostic marker for HCC patients.

Systematic identification of the subproteome of Escherichia coli cell envelope reveals the interaction network of membrane proteins and membrane-associated peripheral proteins.

Membrane proteins of Gram-negative bacteria are key molecules that interface the cells with the environment. Despite recent proteomic identification of numerous oligomer proteins in the Escherichia coli cell envelope, the protein complex of E. coli membrane proteins and their peripherally associated proteins remain ill-defined. In the current study, we systematically analyze the subproteome of E. coli cell envelope enriched in sarcosine-insoluble fraction (SIF) and sarcosine-soluble fraction (SSF) by using proteomic methodologies. One hundred and four proteins out of 184 spots on 2D electrophoresis gels are identified, which includes 31 outer membrane proteins (OMPs). Importantly, our further proteomic studies reveal a number of previously unrecognized membrane-interacting protein complexes, such as the complex consisting of OmpW and fumarate reductase. This established complete proteomic profile of E. coli envelope also sheds new insight into the function(s) of E. coli outer envelope.